Unit 4.2: The Endocrine System and Blood Sugar Regulation Day 1

Agenda Notes: The Endocrine System Immune System and Ebola Spring Break HW due tomorrow Assessment on Thursday and Study Guide and all things immunity due!

Common Threads: Unit 4 #1: Regulation and Control #2: The Cell Membrane #3: Events at the cellular level affecting the whole organism

The Endocrine System The Endocrine System Control and regulation of responses to internal and external stimuli Works in conjunction with the nervous system Helps regulate metabolism, homeostasis, growth, development, reproduction and behavior How? Through chemical signals: Hormones: delivered through circulatory or lymphatic system (long distance) Local regulators: travel by diffusion; effect limited to cells close by

Local Regulators Produced by many different types of cells Cytokines: communication between immune system cells Prostaglandins: multiple functions, including stimulating contraction of uterus and inflammation Growth factors: stimulates cell division and proliferation Nitric Oxide: relaxes blood vessels (vasodialation), increases blood flow

Endocrine Signaling Internal or External Stimulus Your blood sugar goes up You see a bear Reception (signal) Release of Chemical Signal Adrenal Gland releases Epinephrine Pancreas releases insulin Transduction (release) Response Liver releases glucose Liver, fat, muscle cells take up glucose Response

Feedback Mechanisms Two types Positive Feedback Loop: The response to the stimulus increases (+) the response Negative Feedback Loop: The response to the stimulus reduces (-) the response Complete questions 1-7 15 minutes

Hormones Released by structures called glands, or by specialized cells in organs Chemical types: polypeptides (proteins), amines (from amino acids) and steroids Water soluble (amino acids and proteins) or lipid soluble (steroids) Protein receptor receives signal at target cell Cell Membrane receptors (water soluble) Cytoplasmic receptors (lipid soluble) No receptor, no response: Allows hormones to target specific cell types

Water soluble hormone signaling pathway Lipid soluble hormone signaling pathway Change shape= change function

Differences Lipid Soluble Hormones: Water Soluble Hormones Moves through cell membrane Binds to receptor protein in cytoplasm or nucleus Triggers gene expression: causes gene’s to switch on or off Water Soluble Hormones Bind to receptor in cell membrane Triggers series of molecular interactions in cell Generates a response: enzyme activation, activation of transport protein, gene expression

Steroid: testosterone Protein: Growth factor—stimulates muscle cell growth

Reception (signal) Transduction (release) Water soluble Response

Immune System With your group go through the innate and adaptive immune system Make the connection with how Ebola disrupts the immune system.